Anonymous has promised to attack all web assets outside Syria it can identify as belonging to the government. This begins with embassy sites in other nations. As of this morning, it was reported the Syrian embassy site in Belgium was down, but the Chinese one was still operating.

It's impossible to say exactly why the Net shut off has occurred in Syrian, but if the idea is similar to what's happened before in Egypt and Libya, it's an attempt to isolate the population and prevent data sharing from inside Syria to the outside. Syrians inside the country can still find means to access the Internet despite the blackout, but for now the outage seems generally to be holding.